The present invention relates to a ring used to maintain an opening in eyeball tissue in an expanded condition during an ophthalmic procedure.
During ophthalmic surgery, it is sometimes desirable to enlarge an opening in eyeball tissue, such as holding the iris open for access through the pupil. For example, cataracteous lenses can be replaced in a procedure commonly referred to as phacoemulsification, or “phaco” for short. In a phaco procedure access through the pupil is required to insert and manipulate an ultrasonically driven tool to break apart and aspirate the lens. It has been proposed that, at least in some cases, expansion of the opening be achieved mechanically by hooks that engage and pull against edge portions of the eyeball tissue, such as inner edge portions of the iris to expand the pupil during a phaco procedure. See, for example, the hooks disclosed in U.S. Pat. No. 5,716,328.